High Liquid Temperature Relief Valve # TOT-VLV-1/4ECONO-HAT/RA-105M/F. The model ECONO/HAT/RA reverse acting mechanical (self-operating) temperature valve requires no outside power. It modulates throughout the temperature range to conserve liquid media, yet will eliminate large quantities of over-temperature liquid if required. It is unaffected by pressure variations and costs 50 – 75% less than electrical substitutes. The ¼" ECONO/HAT-RA valves are commonly used to provide thermal relief for booster pumps. Pumps must be sized for maximum expected flow rates so much of the time, pumps are idling against a dead head or much lower than design flow. In such cases, the pump energy is transferred into heating the water in the pump casing. When pumps run under such reduced flow conditions, the water temperature inside the pump casing can easily reach dangerous temperatures. The result can be damaged seals or even more serious pump damage. Another serious concern may be exposure of humans to the elevated water temperature from the pump when operating water spigots, showers, and other such water supplies. Human exposure to 140°F water can cause serious 3rd degree burns to skin and tissue in just 5 seconds! The ECONO/HAT-RA valves are self-operating so no power or signal connections are required. Simply screw the valve into the pump housing so it senses water temperature in the pump and run the outlet from the valve to drain or low pressure return. If the water temperature exceeds the valve setpoint, the valve automatically opens to allow cooler supply water to refill the pump as the hot water is discharged. The ECONO/HAT-RA will automatically close when water temperature falls below the setpoint to conserve water and reduce waste. These valves are very easy to install and offer an economical solution to this common problem. Therm-Omega-Tech also offers other similar valves for higher flow rates and pressures
OPERATION: As the fluid temperature increases to within the operating range of the ECONO/HAT-RA, the thermal actuator modulates the valve open. If the fluid temperature is above the acceptable range, the valve will continue to modulate open allowing additional fluid discharge. As the outlet temperature falls slightly, the valve then modulates toward the closed position, reducing flow. This modulating action maintains a relatively constant fluid temperature even as operating conditions vary.
Construction: All brass body, fittings, stainless steel spring and plug
Connections: 1/4 NPT MALE inlet and 1/4" NPT female outlet
Maximum Operating Pressure: 300 PSI
Open: 105 degrees Fahrenheit
Close: 95 degrees Fahrenheit
Dimensions: 1" diameter, 3-1/2" long
Weight: .35 lbs
Install thermal relief valve as close to the pump casing as possible to avoid delay in response. Male NPT inlet may be screwwed directly into the pump casing. The outlet from the relief valve should be piped to a drain or return line at lower pressure than the pump inlet.